Portable electronic instruments, such as electronic test equipment, often use a battery as a source for electrical power. The battery is generally heavy and is usually stored in a battery compartment. Since the battery is heavy, it may sometimes come out of the battery compartment if it is not restrained when the electronic instrument is subject to a shock caused, for example, by dropping the instrument. The battery is normally restrained by a cover that is mounted in a cover frame which is part of the electronic instrument and which defines an opening in the battery compartment.
A conventional cover assembly including a cover and a cover frame is shown in FIG. 1 restraining a battery 10 in a battery compartment 12. The cover assembly includes a cover 14 and a cover frame 16. The cover 14 has a tongue 18 at one edge that fits into a groove 20 formed in the cover frame 16. A latch 22 mounted on the edge opposite the tongue 18 engages to a catch 24 which is also formed in the cover frame 16. Because the battery 10 is heavy, it exerts a force F on the cover 14. The latch 22 and the tongue 18 directly bear the force F from the battery 10 to restrain the battery 10 in the battery compartment 12.
This force F that is exerted directly on the cover 14 may cause problems for the conventional cover assembly. Because the latch 22 directly bears the force F from the battery 10 on the cover 14, large forces F exerted of the battery 10 toward the cover 14 may disengage the latch 22 from the catch 24, allowing the cover 14 to open and the battery 10 to fall out of the battery compartment 12. The stress on the latch 22 from bearing the force F from the battery 10 may also tend to wear the latch 22 out prematurely. Also, because the latch 22 is a prominent feature on the cover 14, the latch 22 may sometimes disengage from the catch 24 if it is struck. This can also happen if an electronic instrument using the conventional cover assembly is dropped on the ground. Further, in order to best restrain the battery 10 in the battery compartment 12, it must be held snugly by pressing the battery 10 into the battery compartment 12. Because the latch 22 bears the force F from the battery 10 on the cover 14, the battery 10 must be pressed into the battery compartment 12 at the same time the latch 22 is engaging to the catch 24. This makes it unnecessarily difficult for the latch 22 to engage to the catch 24. Finally, opening the cover 14 takes three threes or motions. A first force exerted inwardly on the cover is required to unload the cover, a second motion is required to disengage the latch 22 from the catch 24, and a third motion is required to open the cover 14.
Therefore, there is a need in the art for a cover assembly of simple construction which overcomes these problems.
One object of the invention is to provide a cover assembly which consistently restrains an object, such as a battery, in an enclosure, such as a battery compartment.
Another object is to provide a cover assembly which does not wear out from a force on the cover assembly from the object.
A further object is to provide a cover assembly for an electronic instrument which does not fail if the electronic instrument is inadvertently dropped.
Still another object is to provide a cover assembly which is easy to use.
Additional objects, advantages, and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized mad obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.